\documentclass[11pt,a4paper,oneside,fleqn]{book}

%% Document setup
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{graphicx}
\usepackage{makecell}
\usepackage[top=2cm, bottom=2cm, left=3cm, right=2cm]{geometry}
\usepackage{a4wide}
\usepackage[dutch]{babel}
\usepackage[T1]{fontenc}
\usepackage{xtab}
\usepackage{amsthm}
\usepackage{url}
\usepackage[utf8]{inputenc}
\usepackage[small,bf,hang]{caption}
\usepackage{fancyhdr}
\usepackage{float}
\usepackage[table]{xcolor}
\usepackage{hyphenat}
\usepackage{lscape}
\usepackage[square,numbers]{natbib}
\usepackage{hyperref}
\usepackage{framed}
\usepackage{color}


\pagestyle{fancy}
\fancyhf{}
\renewcommand{\headrulewidth}{0pt}
\fancyhf[HL]{\nouppercase{\textit{\leftmark}}}
\fancyhf[FC]{\thepage}

\setlength{\parindent}{0pt}
\setlength{\headheight}{14pt}

% User defined methods
\newcommand{\npar}{\par \vspace{2.3ex plus 0.3ex minus 0.3ex}}
\newcommand{\package}[1]{\texttt{#1}}
\newcommand{\class}[1]{\nohyphens{\texttt{#1}}}
\newcommand{\file}[1]{\nohyphens{\texttt{#1}}}
\newcommand{\interface}[1]{\nohyphens{\texttt{#1}}}
\newcommand{\enum}[1]{\nohyphens{\texttt{#1}}}
\newcommand{\method}[1]{\nohyphens{\texttt{#1}}}
\newcommand{\constant}[1]{\nohyphens{\textsc{#1}}}
\newcommand{\degrees}{\ensuremath{^{\circ}} }

\begin{document}

\pagenumbering{alph}
\input{front_page.tex}

\frontmatter
\newpage
\tableofcontents
\newpage

\input{sections/abstract.tex}
\input{sections/introduction.tex}

\mainmatter 

\input{sections/idp.tex}
\input{sections/nusmv.tex}
\input{sections/reflections.tex}

\appendix

\backmatter

%\bibliographystyle{plain}
%\renewcommand{\refname}{Referenties}
%\bibliography{references}
%\nocite{*}
\end{document}